1 RESISTANCE OF COMPACTED ASPHALT MIXTURES TO MOISTURE-INDUCED DAMAGE AASHTO T 283 GLOSSARY Tensile strength -- a measure of the force required to pull apart a material. SCOPE HMA made from certain materials may be sensitive to the presence of water in the finished pavement. Water will cause the binder to not adhere to the aggregate. Since the binder is the "glue" that holds the pavement together, rapid failure of the pavement can be expected if the binder cannot adhere to the aggregate. This is often referred to as stripping. To help prevent stripping, additives such as hydrated lime or liquid anti-stripping chemicals may be required. AASHTO T 283 is a test method that can be used to determine if the materials may be subject to stripping and also to measure the effectiveness of additives. The test is performed by compacting specimens to an air void level of six to eight percent. Three specimens are selected as a control and tested without moisture conditioning, and three more specim,ens are selected to be conditioned by saturating with water undergoing a freeze cycle, and subsequently having a warm-water soaking cycle. The specimens are then tested for indirect tensile strength by loading the specimens at a constant rate and measuring the force required to break the specimen. The tensile strength of the conditioned specimens is compared to the control specimens to determine the tensile strength ratio (TSR). This test may also be performed on cores taken from the finished pavement. SUMMARY OF TEST Apparatus Vacuum container for saturating specimens Balance, general purpose class G 2 (AASHTO M 231) Water bath, capable of maintaining a temperature of 140 ± 2°F (60 ± 1°C) Pans, having a surface area of 75-200 in 2 (48,400 – 129,000) mm 2 in the bottom and a depth of approximately 1 in. (25 mm) Loading jack and force measuring device Loading strips with a curved face to match the side of the specimen
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